Patella

Question 1

Projections for the Patella

Answer 1

•PA Projection
•PA Oblique Projection (Medial Rotation)
•PA Oblique Projection (Lateral Rotation)
•Hughston Method (Tangential Projection)
•Merchant Method (Tangential Projection)
•Settegast Method (Tangential Projection)
•Sunrise Method (Tangential Projection) Mountain/Skyl ine View

Question 2

PA Projection
Part Position

Answer 2

• Prone
  Part Position:
• Center the IR to the patella.
• Adjust the position of the leg to place
  the patella parallel with the plane of the IR. This usually requires that the heel be rotated 5 to 10 degrees laterally

Question 3

PA Projection
Central ray

Answer 3

Perpendicular to the mid popliteal
area exiting the patella.

Question 4

_____ projection of the patella
provides sharper recorded detail than in the AP projection because of a closer object-to-image receptor distance (aID)

Answer 4

PA

Question 5

PA Oblique Projection (Medial Rotation)
Part Position

Answer 5

• Prone
  Part Position:
• Knee flexed 5-10°; knee 45-55°
  medially

Question 6

PA Oblique Projection (Medial Rotation)
Central Ray

Answer 6

Entrance: Patella Angulation: Perpendicular

Question 7

• Medial portion of patella free of
  femur

Answer 7

PA Oblique Projection (Medial Rotation)

Question 8

PA Oblique Projection (Lateral Rotation)
Part Position

Answer 8

• Prone
  Part Position:
• Knee flexed 5-10°; knee 45-55°
  laterally

Question 9

PA Oblique Projection (Lateral Rotation)
Central Ray

Answer 9

Entrance: Patella Angulation: Perpendicular

Question 10

• Lateral portion of patella free of
  femur

Answer 10

PA Oblique Projection (Lateral Rotation)

Question 11

Hughston Method (Tangential Projection)
Part Position

Answer 11

• Prone
  Part Position:
• Anterior surface of knee against IR;
  knee flexed 50-60°; foot rested against collimator/support

Question 12

Hughston Method (Tangential Projection)
Central Ray

Answer 12

Entrance: Patellofemoral joint
Angulation: 45° cephalad

Question 13

Patella; patellofemoral
joint

Answer 13

Hughston Method (Tangential Projection)

Question 14

Purpose:
- To demonstrate subluxation of patella & patellar fx
- It allows assessment of femoral condyles

Answer 14

Hughston Method (Tangential Projection)

Question 15

Merchant Method (Tangential Projection)
Part Position

Answer 15

• Supine
  Part Position:
• Both knee flexed 40° or between 30-90° (to demonstrate various patellar disorders)
• IR resting on patient’s shins; uses IR holding device & axial viewer device

Question 16

Merchant Method (Tangential Projection)
Central Ray

Answer 16

Entrance: Midway between patellae at level of patellofemoral joint
Angulation: 30° caudad from horizontal

Question 17

Femoral condyle;
intercondylar sulcus & magnified non distorted patellae

Answer 17

Merchant Method (Tangential Projection)

Question 18

Settegast Method (Tangential Projection)
Central Ray

Answer 18

Entrance: Joint space between patella & femoral condyles Angulation:
- Perpendicular (if joint is
perpendicular);
- 15-20 cephalad (if
joint isn’t
perpendicular)
- Angulation
depends on knee flexion

Question 19

Purpose:
- Useful for demonstrating
vertical & transverse fx of
patella
- Useful for investigating
articulating surfaces of patellofemoral articulation

Answer 19

Settegast Method (Tangential Projection)

Question 20

Sunrise Method (Tangential Projection) Mountain/Skyl ine View
Part Position

Answer 20

• Supine/Sitting
  Part Position:
• Knee flexed 40-45°

Question 21

Sunrise Method (Tangential Projection) Mountain/Skyl ine View
Central Ray

Answer 21

Entrance: Patellofemoral joint Angulation: 30° from horizontal

Question 22

Purpose:
- Joint space between patella & femoral condyles

Answer 22

Sunrise Method (Tangential Projection) Mountain/Skyl ine View